When a fluoroscopy is performed with an X-ray CT apparatus, as shown in FIG. 1, during which an X-ray tube 1b and an X-ray detector 2a are rotated to acquire data for producing an image, an operator stabs a biopsy needle N into a subject K.
A hatched region in FIG. 2 represents a space through which the X-ray passes during one rotation of the X-ray tube 1b and the X-ray detector 2a. As will be understood from FIG. 2, there is a problem in that the operator is exposed to the X-ray because the operator's hand lies in the space through which the X-ray passes.
In order to decrease an X-ray radiation dose to which the operator is exposed, it is desirable to set the X-ray radiation dose low. However, this will cause another problem in that data cannot be acquired with a good S/N ratio and the image quality is deteriorated.